Sep 10, 2011

A university professor who carried out a major study into the evacuation of the World Trade Centre after 9/11 says the "far-reaching impact" of the attacks is still being felt when it comes to the design of new high-rise buildings across the world.

Professor Ed Galea, from the University of Greenwich, led a three and a half year study into the evacuation of the twin towers, a collaboration between the universities of Greenwich, Ulster and Liverpool.

The project included in-depth interviews with 271 survivors about their experiences of what it was like as they tried to leave the buildings. Their personal stories helped the research team to paint a comprehensive picture of how people acted and what factors influenced their behaviour during evacuation, and assisted in identifying key safety issues that building designers need to address.

"The research is still ongoing and the data we have collected, both on the mechanics of a large-scale evacuation, and on the issues human behaviour, is being shared across the world, as a valuable international resource," Professor Galea says.

Using their buildingEXODUS evacuation software, the Greenwich team analysed the evacuation dynamics of the events of 9/11 and also explored what may have happened if the buildings had been fully occupied. From this work, Professor Galea concluded that, for buildings above a critical population and height, stairs alone were not sufficient for safely evacuating the entire population.

Alongside colleagues Dr Peter Lawrence and Mike Kinsey, at the university's Fire Safety Engineering Group, Professor Galea went on to explore the use of lifts for evacuations in high-rise buildings. As part of their buildingEXODUS software, the researchers have developed advanced human behaviour models, which simulate the choices people make in deciding to use a lift/elevator as part of their evacuation route in an emergency.

"Our studies suggest that buildings should utilise elevators and stairs, in combination," Professor Galea says. "We know stairs alone are not sufficient for full building evacuations, and since 9/11 there has been a trend to use specially designed elevators. But elevators, even fire safe elevators, raise the complex issue of human behaviour, and we know from our studies that many people do not trust using them, or will simply not wait for them, in an emergency.

"So it's vital to consider all aspects when designing new buildings. This means not just the mechanical issues of using elevators to evacuate people, but the whole issue of human behaviour, and this is what we have built into our computer modelling."

Professor Galea, Founding Director of the Fire Safety Engineering Group, warns that, ten years on from 9/11, people need to guard against complacency. "Evacuation drills and training always need to be taken extremely seriously, as successful evacuation depends in part on how quickly people respond," he says. "We found in our research that some people took many minutes to decide to evacuate the towers, while others didn't know where the stairs were, for example. The attacks have also highlighted the need for better information systems in buildings, with proper instructions in an emergency, rather than just an alarm going off.

To state that we live in a different world than we did before September 11, 2001, (or that America is “different”) is both self-evident and uninformative. Yet we hear it continuously, the speakers (often politicians and government officials) using the phrase as if expressing a profound truth instead of a trite platitude.

How much was America changed by the 9/11 attacks? It depends on whether you're talking about the American government or the American people. The government has of course changed greatly -- mostly in the realm of national security; air travel is the most obvious example, with reinforced cockpit doors, invasive security screening, and armed air marshals. The government's reaction (many would argue overreaction) to the attacks has cost blood and treasure unprecedented in world history. America as a country will certainly never be the same.

But the picture for Americans is a very different matter. Contrary to popular opinion, very few American’s personal lives were changed.

According to a Washington Post-ABC News poll conducted just three months after September 11, only slightly more than half of Americans surveyed said that the attacks changed their personal lives. Even more remarkably, two-thirds of those surveyed said the country had changed for the better; they believed the 9/11 attacks had actually done America more good than harm in the long term. (This probably reflected the popular but short-lived sentiment that Americans had unified around a common enemy.)

Seven months after the attacks, only one in five teenagers said that the 9/11 attacks directly affected their lives, according to a telephone survey of 1,003 high school students conducted for the Horatio Alger Association. An October 10, 2001, ABC News article, “Lingering Emotions,” reported a poll that found that “Nearly half of Americans surveyed—44 percent—say the attacks…had no lasting impact on their mental health.” By January 2002 almost 90 percent of Americans in a CBS News poll said that their lives had returned to normal or never changed after the attacks, and according to a study published in the Journal of the American Medical Association, six months after the attacks nearly 95 percent of Americans living outside of New York City reported no significant lingering symptoms related to stress from the attacks.

Thus the idea that most American's lives profoundly changed after 9/11 is simply a patriotic myth. That’s not to say that some people (especially those in Manhattan at the time) were not, and are not, sincerely devastated by the attacks—just that they are not representative of most Americans. For most who were traumatized in the months after the attacks, any lingering pain has faded in the decade since.

Sep 9, 2011

In the fall of 2001, the United States was confronted by two major public health challenges: the anthrax mailings and threat of a biological attack, and the subtler but ultimately more harmful plume of toxic dust that that rose from Ground Zero. The country was prepared for neither.

In the months and years that followed, bioterror proved to be the easier threat to confront, or at least to spend money on. The plume’s damage was harder to address, not least because government officials prematurely insisted on its safety. In both cases, one theme is universal: The wrong decisions were made, and lessons have been incompletely learned.

“I keep getting asked: Are we safer today than on 9/11?” says Laurie Garrett, the Pulitzer Prize-winning author of I Heard the Sirens Scream, a new book on 9/11 and its public health aftermath. “My answer is that we’ve spent an enormous amount of money, but I’m not at all convinced that the expenses have made us safer.”

Wired.com talked to Garrett about biodefense, the Ground Zero plume and what can be learned.

Wired.com: What is the big, takeaway lesson?

Garrett: There used to be this big debate regarding our national defense: Can the Pentagon fight a two-front war? Back then, it was always couched in terms of whether our military forces could be stretched so thinly. I would ask the same of our public health forces, our first responder forces, our medical forces — and I would say that the answer is no.

What we see, when you look at the lessons of 9/11, is that these people were burning candles at both ends. They were thoroughly exhausted. We demanded of our public health personnel a scale of performance that lasted for weeks. And one of the things that was really startling for me in the research to I Heard the Sirens Scream was how extremely strapped our public health people in New York City and Washington, DC were before the attack.

Afterwards, our health departments, our forensics departments, were all on full alert. They didn’t go off alert until well after Thanksgiving. Many were essentially running on fumes. I think they would say that a lot of decision-making suffered out of exhaustion.

I also spent a lot of time looking at health departments that weren’t targeted, but still went on full alert and stayed there for weeks. And they were so strapped by all the hoaxes, all the phony anthrax letters, all the honest, scared people who thought they were sick. Every one of those reports had to go to a lab.

Wired.com: So in the immediate aftermath, we were shorthanded. But the Bush administration soon established a biodefense program. Did it take the right form?

Garrett: What we found out after 9/11, after the anthrax mailings, and what resonated again with Katrina and every major threat we’ve faced, is that it all comes down to human beings.

Both private and public investors are often are often taken with high-tech answers. They love to invest in sensing devices and diagnostics and vaccines, in robotic bomb searchers, in all these devices that can sense explosives or anthrax in the air. A hell of a lot of money went into both Department of Defense spending, Health and Human Services spending. Everybody was spending billions of dollars, basically on technology, and technology is only as good as the personnel you have. You need a well-trained, well-paid, substantial infrastructure to use the technology and interpret what the technology is saying to them. You can’t take somebody who is paid $15 and hour and has a job description filed a couple notches above janitor and think that this individual can be held responsible for stopping al-Qaida.

Wired.com: Is al-Qaida even the right threat to be worried about? Don’t we have more to fear from a natural pandemic?

Garrett: Before 9/11, old-guard bioterror experts used the phrase dual-use to refer to difficulties in surveillance and verification: The same place that made pharmaceuticals could make biological weapons. But now the phrase gets used differently. People talk about bang for their buck. They say, “This expenditure is good for everyday health as well as this terrible thing that may happen one day.”

Dual-use now tends to justify stockpiling vaccines and purchasing technology. But I would say the appropriate use of the phrase is that the people you will rely on — to protect Americans, to solve great biological mysteries, to determine the appropriate responses — are the same people you rely on every single day to make sure the water coming from your tap is safe to drink, that the air around your building is safe to breathe, that the food you buy at your grocery store is safe from salmonella.

I keep getting asked: Are we safer today than on 9/11? My answer is that we’ve spent an enormous amount of money, but I’m not at all convinced that the expenses have made us safer. And on the public health side in particular, I’m sure the majority of expenditures can be characterized as a complete or borderline waste of funds.

Wired.com: Give me an example.

Garrett: One of the major thrusts of the response to anthrax was responding to smallpox. We spent a couple billion dollars on vaccines, on bifurcated needles, on testing, on every imaginable aspect of new product development. This constituted a huge deployment at the National Institutes of Health and Centers for Disease Control and Prevention.

But the current generation of public health and medical workers had never done a smallpox vaccination. People had no idea how. It’s not just a shot. You don’t even carry out the vaccine process the way you do polio. There’s a whole biological and epidemiological strategy that has to be executed.

People often talk about how all the years spent training, at huge cost, public health workers and hospital workers all over America, to execute this massive effort, constituted dual-use and somehow weren’t a waste of money. Really? Because it turns out the way you’d carry out a vaccine campaign for smallpox isn’t the way you’d carry out of a flu immunization. We learned that during the H1N1 swine flu outbreak.

Wired.com: So it would have been better to hire nurses and doctors, to research pathogens and improve disease surveillance networks.

Garrett: Absolutely. But here’s the catch-22: Some communities that were underserved historically, such as the state of West Virginia, were able to hire workers and boost their state health departments. And then the states cut their budgets, because they were getting federal money. Then, when the feds got wind of this, they started penalizing local jurisdictions, demanding that they spend their money on bioterrorism — “You can’t spend money on mammograms and syphilis monitoring and infant health. How dare you!”

I remember being in a conference in Durango, Colorado. All the people there were freaked out because they’d had the first cases of West Nile viruses appear in the area. But the governor had cut public health budgets across the state. The threat of a real virus was overwhelming them, and they had nobody to track it. And that’s a typical example.

Every aspect of American infrastructure, especially health, is genuinely capable of performing multiple functions and has to be funded accordingly and sustainably so. But we’re seeing the opposite. Budgets are getting hacked right and left. Health departments are cutting right and left.

By hijacking planes from U.S. airports on Sept. 11, 2001, and flying them into the Pentagon and the World Trade Center, terrorists killed thousands of innocent people and first responders and revealed an ugly truth: Our airports were not safe.

Today, thanks to a decade of American ingenuity and innovation, many of those security holes have been patched.

Airports are using new technologies, like refined X-ray backscatter equipment, which enables intimate searching of a passenger without the need for them to strip or be stripped by federal agents.

Soon, removing your footwear and coat and throwing away your bottled water, will be a “thing of the past” for air travelers in the U.S., said Peter Kant, executive vice president of Rapiscan Systems, which is working with the Transportation Security Administration (TSA), to improve gate security.

“There’s new machinery in process that will allow screened passengers to keep their shoes on while moving through checkpoints,” Kant told FoxNews.com.

Those baggage handlers may still "touch your junk," but tremendous changes have made air travel safer and securer.

Behind the scenes at LAX's Terminal Five, computing giant Siemens AG installed new baggage screening systems that let passengers drop off their luggage as soon as they get to the airport.

“Delta Airlines found that they went from processing 200 to over 500 bags an hour with this system,” Megan Zaroda, a spokeswoman for Siemens in New York City, told FoxNews.com. “TSA said that it’s removed congestion and minimized safety risks in airport lobbies.”

Yet another technology coming to the nation’s airports: video surveillance equipment that lets the feds detect “abnormal” behavior in crowds, said Michael Silevitch, a professor at Northeastern University in Boston, and co-director of ALERT, a Department of Homeland Security-funded science and technology R&D center.

“This technology was used successfully, after the fact, to identify the Times Square bomber from the rest of the crowd,” Silevitch said.

And new sensors will identify dangerous individuals who have “explosive residue” on their clothing, so would-be bombers don’t even get into an airport, he said.

“These portable sensors could be used outside of the airport itself to identify dangerous individuals or vehicles before they get close enough to do damage,” he added.

Technology gurus aren't promising that TSA will no longer touch your “junk,” as software programmer John Tyner said last fall after an incident with agents at the airport in San Diego. But they do foresee a kind of return to normalcy at the nation’s airports, and even cargo ports, in the coming years.

Funding for so-called “port security” has increased by about 700 percent in the last 10 years, according to an estimate provided to FoxNews.com by the Georgia Center of Innovation for Logistics, a department of the Georgia Center for Economic Development.

Most of this funding comes from the government and agencies like the U.S. Customs and Border Patrol, the U.S. Coast Guard, and the port authorities that own, maintain, and manage the physical infrastructure of airports, bus terminals and seaports.

The federal government spent $259 million on port security efforts in fiscal year 2001; by 2005 the figure had climbed to $1.6 billion per year, and that has increased under the current administration. The money has gone to port authorities in New York, New Jersey, Philadelphia, Baltimore, Miami and New Orleans. And of course, the Department of Homeland Security itself was created after 9/11.

Private sector firms that operate terminals have also invested heavily in IT security during the last 10 years. For cargo screening, for example, new technologies include "non-computed tomography transmission X-rays," explosive trace-detection devices, large-scale gamma ray machines, and even hand-held radiation detection devices, Anne Isenhower, a spokeswoman for the Georgia Center of Innovation for Logistics, told FoxNews.com.

The 10th anniversary of 9/11 is an emotional landmark for many people. We at Discovery News wanted to find ways to address the painful date in our content -- from slide shows to first-hand accounts of that day to analysis of how the event will be remembered for years to come. We also wanted to hear from you -- and we did.

We asked for your memories of that day and many of you wrote in. We heard from police officers, parents and students from all around the world. Thank you for helping us remember that day and marking this difficult anniversary. And if you didn't get a chance to contribute your thoughts and memories, please post them in the comments below.

The day before, had met with the doctor to find out my husband's cancer was terminal. Had talked with our two children that same evening. The morning of the 11th, I was driving my son to school with the radio on and we heard the first tower going down but wondered if this was an act like The War of the Worlds and maybe we'd missed the intro. We looked at each other in disbelief when we then heard the second tower hit. Our world was already in chaos, now the whole world was as well.

-Louanne Grand

My daughter was about 5 weeks old and it was around 6 a.m. I was changing her diaper and she started laughing for the first time as I tickled her feet. As we were bonding, my husband called me into the living room to see the news--towers collapsing.

- Carolanne Brandt

On the morning of September 11, 2001, I'm in my ninth grade science class. It's my home room, or the first class of the day. My teacher turns the television on and shuts the lights off. Most classes don't have television sets, but we do. I wonder why that is. We watch replay after replay of Flight 11 crashing into the North Tower.

I'm trying something new that year, going for a new look, a new identity. I'm learning to skateboard—nothing against skateboarders—and I'm in a punk rock band—nothing against punk rock music. A guy by the name of Steven sits in front of me. He's a tenth grader, but for one reason or another he's in my ninth grade science class. Steven is the kind of guy I want to be, the character I'm trying to become. Seconds after the television is turned on, before I have time to fully process what I'm watching, I lean forward and whisper to Steven, "Anarchy." He laughs, and I instantly feel dirty, guilty, like an adulterer or a baby shaker or something.

The guilt only grows as we continue watching the news. The higher the plumes of smoke reach the more intense my guilt becomes. One of the greatest tragedies in our country's history, and the first word out of my mouth is anarchy, a joke. I've never shared that story until now, ten years later. I was ashamed. I'm still ashamed.

We continue watching the news, a class of ninth graders and one tenth grade guy I no longer want to emulate. Flight 175 collides with the South Tower and the screen freezes. The bell rings. Kids walk the halls, stunned faces belonging to those with brains developed enough to process the tragedy, while laughter and jokes bellow irreverently from students who can't seem to separate the news coverage from an Arnold Schwarzenegger movie.

- Sean Bess, Birmingham, AL

I had to go to work on 3rd that night ... I was a cop. Over the radio we heard that an unidentified boat was blacked out and headed toward the nuclear station. The cop with me called his wife and told her to pack up and head west as far as they could go. We kept getting updates on the radio. I was absolutely terrified. This was something I couldn't shoot or wrestle to the ground. We were standing in the parking lot of the PD when two jets flew RIGHT over our heads ... I was shaking so hard it was almost impossible to stand up. A few minutes later the dispatcher came over the radio and said that it had all been a drill ... I was SO relieved but the knowledge that that could happen chilled me for weeks.

- Anna Bowen

I saw it on TV and first thought was -- this is a set up. I still can't believe that those jets were hijacked and used as weapons in perhaps the most guarded and secure sky in the world. Sorry for all the lost innocent lives.

-- Ivaylo Grancharov

I was home that day and reading the teletext on the TV when I read that a plane had crashed into one of the towers. I thought it must have been a light aircraft or something. A while later a new bulletin came on that had live footage of the first crash. As I was watching the second plane came into view and hit the building, too. I could hardly believe what I was seeing, at first. It looked like some sort of disaster film rather than real life. I think we're hardened to seeing such images in Hollywood films but then when you see it really happening in real life it takes you a second or two before it registers. I STILL didn't realize it was a terrorist thing, though. I thought at first it must have been some malfunction with auto-pilots or the plane itself. Again, I don't think you can comprehend that anyone's thinking can be so alien to the way most of us think and how they cease to see people as people -- with lives, loves, parents, children, etc. -- and seek to slaughter them simply because they represent 'the enemy'

- Adam Nicke

I live in South Africa, and my memories are almost the same as Adam N. Can't remember if someone phoned me to turn the TV on, as I was working in my home office, but I was shaken to the core. I just kept saying 'oh, my god', I just could not grasp what I was seeing and as he says, as I was watching the live feed with the commentator describing the scene behind him [from a balcony somewhere or something?], someone there shouted 'my god, another one and you could see it happening right behind the commentator and he was turning round in shock and horror. I had my two small kids with me, 6 and 4, and they were sitting watching, which was not really a good thing, but I don't think they really understood what was going on being that age - the sheer monstrous, horrendous import of what we were seeing did not really compute, as it doesn't at that age. I just could not tear myself away from the screen, and I was crying, and I stayed watching as the towers collapsed even. It was too real to be a put up job, and to this day, I can see it unfolding in my mind's eye and wonder, as someone else here says, at the workings of the minds of the people who planned and committed all that. Thank goodness the third plane did not make it thanks to the brave passengers on board. And then there was the other plane...

- Corinna Beamish

We lived across the Raritan Bay from Staten Island/Manhattan, etc..my three memories of that day, the tears, the gorgeous blue skies as a backdrop to all the smoke and death, and a jet fighter screaming over my head at tree level on the way to NY.

- Jackie Nagy

I remember being 9 years old on 9/11, my mum came out to hurry me inside after being at school in the afternoon September 12th New Zealand time to show me what had been happening over the past few hours live on TV. I didn't know what to think at the time being that age, but it affected every single person on the face of the earth some way or another, and it still does to this day.

Sep 8, 2011

Glykeria Manis is a New Yorker through and through. I became good friends with her when I lived in New York a number of years ago. Glykeria was born on the far Upper West Side to Greek immigrant parents. She grew up near the Cloisters of Manhattan, went to high school at The Dwight School, graduated from Columbia University and Hunter College. On September 11, 2001, she was 22 years old and working as an assistant to a railway engineer at the Washington Group International, an engineering firm that occupied the 91st floor of 2 World Trade Center. When American Airlines Flight 11 hit 1 World Trade Center, she was making copies in an interior room. This is her account of that day and her experience in the aftermath.

“I was in the copy room for two minutes and when I came out, I saw a bunch of people at the windows. Where my desk was located, we had a perfect view of the first building. There were a bunch of coworkers gathered around my desk, watching in a sort of trance, in shock. The first thing I saw was a hole in the east side of the first tower that was growing. The steel of the building was peeling off like a banana and falling. It started getting bigger and then everything started getting sucked out of the building: papers, CDs, computers and eventually people.

“This one guy had his nosed pressed up against the window. You could feel the heat emanating from the glass. When the first man jumped, I watched my coworker as the body dropped. He was following the guy with his eyes. He may have seen the guy fall completely. I was standing a few feet from the window and couldn’t see all of the way down. It was at that moment another guy in the group said, ‘Lets’ get the f**k out of here.’ Everyone scattered.

“A coworker was next me, a Chinese man, mid-50s, an engineer with a very calm personality. I looked at him and said, ‘I don’t know where the stairs are. Can I walk with you?’ He said sure. I grabbed my sweater and purse, he came with his briefcase and we started toward the stairs.

“On a normal day, for me to get down to the lobby, I had to take the local elevator from the 91st floor to the 76th floor, and then transfer to the express elevator to lobby. When we got into the stairwell, I realized I’d have to walk all the way down. As were getting lower, more and more people started entering the stairwell.

"People were acting completely random. Women were going down the stairs in stilettos. I thought, ‘Why don’t you just take off your shoes? Everyone could walk more quickly that way.’ One guy started pushing people to get down faster. This other lady was reaching over my shoulder to grab the woman in front of me. I figured they were friends, so I asked her, 'Would you like to step in front of me?' I thought that was easier than reaching over my shoulder and risking all of us taking a tumble down the stairs. Why didn't she think of that?

“At one point it hit me really hard: ‘I have to get out NOW!’ It hit me in my heart, in my chest. When I looked up, it said Floor 76. I pulled myself out from the stream of people, reached through the crowd, grabbed my coworker’s hand, and pulled him out.

“I said, ‘OK, I think we should take the elevator but I’m scared.’

“He said, ‘Ok, we’ll open the door, and if it’s safe, we’ll go out.’

“We didn’t know what kind of hell we were going to see. I wanted to get out of that stairwell, but I was scared, and I knew I was taking a really big risk. I had a coworker tell me later that he had been in the elevator and as soon as they got to the lobby, the second plane hit. We decided that if it didn’t look safe, we wouldn’t go through the door.

“We opened the door, and there was not a single person on the floor. Normally there were security guards. But it was so quiet, it was eerie. I looked to the left, and out the window the only thing I could see was blue. Clear sky. Peaceful. It was so beautiful and peaceful that it scared the s**t out of me.

“All of sudden I heard ‘ding.’ Directly across from us, the elevator doors opened. I hadn’t even seen them. We went in and immediately the elevator filled with people who followed us. It was jammed packed in there and it was silent. Nobody was speaking. You could feel the tension in the air; it was so heavy. All I kept thinking was, ‘Is this elevator going to make it down?’ I knew there was a chance I could die, but I also thought that if I had stayed on the stairs, I would die. I believe that if I hadn’t been with my coworker, maybe I would have stayed on the stairs. Maybe having another person there who was calm helped me make that decision.

“When the elevators finally reached the bottom, I thought, ‘Let’s go let’s go let’s go let’s go let’s go.’ We wanted to exit through the south doors, but the fire department redirected us. I went out the east door because that was the next closest doorway to me, but some people went north toward the plaza. I didn’t go out toward the plaza. Later, people said that it was a sea of blood and body parts, the whole plaza had turned red. When I opened the door to exit on the east side, I looked at my feet stepping out onto the concrete. I took a huge breath of air, my lungs filled with it. I couldn’t believe I made it out. ‘I’m out!’ I thought.

“I was standing with my back up against the door I had just exited. It was all open in front of me. I felt like I was in a war zone. I wondered, ‘Where do I run? Where do I go where it’s safe?’ Even though I wanted to get away from what was behind me, in front of me was open space. If I ran out, I’d be exposed. Maybe this is why some people lingered. People told me later they didn’t know where to go.

“In front of me there was a couple, they were looking at the building and the girl was pointing. I could see the look on her face was pure terror. I told myself, ‘I’m not going to look. If that’s what’s going on behind me, I’m going to keep going forward.’ I put my hand over my head in case there was flying debris and I said to myself, ‘Just go!’

“In the moments when I was at the door and crossing the street, there was a surreal, slow-motion quality; everything felt like it was taking a lot longer to happen. It was like a movie where you could see things, but you couldn’t hear them. Maybe it was two or three minutes, but it felt like half an hour. Time was different. Space was different. The fact that it was surreal might be why people were unable to respond. When something is outside your normal experience, you don’t know how to respond, you don’t have a point of reference.

“I crossed Church Street along the east side and got to the northwest corner of Cortland and Church Street. I ducked under the overhead in front of the Brooks Brothers. When I got there, I felt it was safe to turn around. I saw my coworker going up the street. He was already going somewhere else, off in another direction. I saw the chaos growing and more debris was falling out and the hole kept growing. I remember this one man who fell from the first tower. When he fell, it looked like his body was a piece of paper floating down. It was doing this left-to-right 'U' motion. Maybe by that point, he had already passed out. It’s like his body had no life already. I didn’t look to see if he landed. I couldn’t look at that. I turned away. People were taking pictures. A guy was videotaping from Cortland, and I thought, ‘How can you be videotaping this?’

“I walked east along Cortland, toward Broadway, and I was less than halfway up the block when I heard the second plane, the sound of its engine revving up for more speed. It was so loud, it felt like it was exactly above my head, and it forced me to look up. I remember seeing the silver underbelly of a plane. I followed the sound and the silver light toward the building.

"So this is where it gets confusing in terms of what happened. Afterward, everyone said that the plane was going south and made a U-turn and hit the south side of the building traveling north. But I experienced it differently from where I was. I thought I saw it enter the building from the east.

“All of a sudden...BOOM! There was a huge explosion. I never saw anything so red in my life. It was red like blood, like anger. It felt like it was coming through me, it was so powerful. I had just been sitting where it hit. If I hadn’t evacuated when I did, I don’t know if I would have made it out. I thought the whole building was going to explode and land on top of me, and I threw myself to the ground. Once that explosion happened, everyone just started running in every direction. People were screaming and mayhem broke loose. Prior to that, people were panicked, but it seemed like a slow-motion panic. After the second plane hit, it was like somebody hit the PLAY button and the speed of everyone on the street changed. Once I realized I was okay, I got up and continued walking.

“I thought we were under attack. I thought that more buildings were going to be hit. The fact that it took a few minutes between the two attacks, I thought that more planes were on the way. I was trying to figure it out. I started strategizing if I were attacking New York, what would I hit next? Landmark buildings and sites? But then I thought, ‘No, they’re going to hit the bridges, isolate Manhattan and then bomb it.’

“So I decided to head for the Seaport. I wanted to get away from the buildings. I thought if they bomb the bridges, I’ll jump in the water. I was prepared to swim to Brooklyn. On the way, a woman asked to use my cell phone but there was no reception. She said she was a freelance writer for the New York Times. We walked together to the Seaport. I asked her, ‘What are you going to do?’ She said she was going to Queens and had to take the Queensboro Bridge. I said, ‘I’m not getting on any bridge.’

“The Seaport was completely deserted. As I approached, I saw a guy sitting on a bench on South Street. He had his headphones on and was bopping his head to the music and getting into the song. I stared at him, stunned. I tried to use a pay phone but I couldn’t get through to anyone. It wasn’t connecting. I left and started walking north up the FDR Highway. As I was going north, I saw black cars with black-tinted windows speeding down the highway. They were CIA or FBI or something. It was really weird because it was just car after car and there were no other cars on the highway except them and it was like a parade of black-tinted cars. I also passed a police precinct on my left with a big group of officers out front. They must have been getting instructions before heading down to the site.”

A startling mix of human and primitive traits found in the brains, hips, feet and hands of an extinct species identified last year make a strong case for it being the immediate ancestor to the human lineage, scientists have announced.

These new findings could rewrite long-standing theories about the precise steps human evolution took, they added, including the notion that early human female hips changed shape to accommodate larger-brained offspring. There is also new evidence suggesting that this species had the hands of a toolmaker.

Fossils of the extinct hominid known as Australopithecus sediba were accidentally discovered by the 9-year-old son of a scientist in the remains of a cave in South Africa in 2008, findings detailed by researchers last year. Australopithecus means "southern ape," and is a group that includes the iconic fossil Lucy, while sediba means "wellspring" in the South African language Sotho. [See images of human ancestor]

Two key specimens were discovered — a juvenile male as developed as a 10- to 13-year-old human and an adult female maybe in her late 20s or early 30s. The species is both a hominid and a hominin — hominids include humans, chimpanzees, gorillas and their extinct ancestors, while hominins include those species after Homo, the human lineage, split from that of chimpanzees.

To begin to see where Au. sediba might fit on the family tree, researchers pinned down the age of the fossils by dating the calcified sediments surrounding them with advanced uranium-lead dating techniques and a method called paleomagnetic dating, which measures how many times the Earth's magnetic field has reversed. They discovered the fossils were approximately 1.977 million years old, which predates the earliest appearances of traits specific to the human lineage Homo in the fossil record. This places Au. sediba in roughly the same age category as hominids such as Homo habilis and Homo rudolfensis, which were thought to be potential ancestors to Homo erectus, the earliest undisputed predecessor of modern humans. [10 Things That Make Humans Special]

"As the fossil record for early human ancestors increases, the need for more accurate dates is becoming paramount," said researcher Robyn Pickering at the University of Melbourne in Australia.

Small but humanlike brain

Most aspects of Au. sediba display an intriguing mix of both human and more primitive features that hint it might be an intermediary form between Australopithecus and Homo.

"The fossils demonstrate a surprisingly advanced but small brain, a very evolved hand with a long thumb like a human's, a very modern pelvis, but a foot and ankle shape never seen in any hominin species that combines features of both apes and humans in one anatomical package," said researcher Lee Berger, a paleoanthropologist at the University of Witwatersrand in Johannesburg, South Africa. "The many very advanced features found in the brain and body and the earlier date make it possibly the best candidate ancestor for our genus, the genus Homo, more so than previous discoveries such as Homo habilis."

The brain is often thought of as what distinguishes humanity from the rest of the animal kingdom, and the juvenile specimen of Au. sediba had an exceptionally well-preserved skull that could shed light on the pace of brain evolution in early hominins. To find out more, the researchers scanned the space in the skull where its brain would have been using the European Synchrotron Radiation Facility in Grenoble, France; the result is the most accurate scan ever produced for an early human ancestor, with a level of detail of up to 90 microns, or just below the size of a human hair.

The scan revealed Au. sediba had a much smaller brain than seen in human species, with an adult version maybe only as large as a medium-size grapefruit. However, it was humanlike in several ways — for instance, its orbitofrontal region directly behind the eyes apparently expanded in ways that make it more like a human's frontal lobe in shape. This area is linked in humans with higher mental functions such as multitasking, an ability that may contribute to human capacities for long-term planning and innovative behavior.

"We could be seeing the beginnings of those capabilities," researcher Kristian Carlson at the University of Witwatersrand told LiveScience.

These new findings cast doubt on the long-standing theory that brains gradually increased in size and complexity from Australopithecus to Homo. Instead, their findings corroborate an alternative idea — that Australopithecus brains did increase in complexity gradually, becoming more like Homo, and later increased in size relatively quickly.

If you think stinging insects in your garden are big, consider Dalara garuda, a newly identified wasp that's five times bigger than most other wasps, according to a recent Natural History Museum, Berlin, press release. You can see the size difference in the above picture.

The huge wasp was named after "Garuda," a mythical "winged warrior" bird from Indonesia.

Entomologist Michael Ohl identified the pitch black wasp while studying the insect collections at the museum. It was originally collected from Indonesia's Sulawesi Island by Lynn Kimsey of the University of California, Davis.

Males of this wasp species measure 2.5 inches long, or about the same size as a human ring finger in length. Their jaws are impressively large and are said to be even stronger and longer than the wasp's front legs.

"Its body size and jet-black color make this wasp a really disturbing creature," Ohl was quoted as saying in the release.

Little is known about the wasp's behavior, since it was not observed much in the wild, but it's likely that the big jaws play a role in fighting and mating.

The wasp is doubly ferocious since it can both sting and inflict a painful bite with its scissor-like jaws.

"Its jaws are so large that they wrap up either side of the head when closed," Kimsey said.

The discovery of dozens of tiny sharp teeth together with egg capsules proves the existence of a 230 million-year-old shark nursery, according to a paper published in the latest Journal of Vertebrate Paleontology.

The discovery represents the first occurrence of egg remains and young shark teeth in one area.

"It allows the direct correlation between those eggs and the young and the interpretation of the area as a shark nursery," lead author Jan Fischer explained to Discovery News.

Fischer, a researcher at the TU Bergakademie Freiberg's Geological Institute, and his colleagues found the shark remains at the Madygen Formation in southwestern Kyrgyzstan. The region is well known to paleontologists for its exquisite preservation of insects and plants from the Late Triassic, a time when the earliest dinosaurs walked the earth.

The excavated eggs and teeth represent two different types of sharks: hybodontids and xenacanthids.

"Hybodontid sharks are the extinct sister group of modern sharks that superficially resemble modern sharks in body shape except for small horns on the heads of males," Fischer said. Hybodontids were the dominant sharks during the Triassic and Jurassic periods.

Xenacanthids, on the other hand, died out around 210 million years ago.

"They are characterized by an eel-like body shape in contrast to the 'normal' shark shape, and a noticeable spine that protrudes backwards from their head," he said.

The two types of sharks co-existed for quite a while, with females of both apparently depositing their eggs in freshwater streams near ample shoreline vegetation. Modern sharks aren't exactly known for their loving parental care, so the researchers believe females returned to nearby lakes or other streams while their young hatched on their own, staying in the nursery area until they grew and then later joined adults.

"We may speculate that they formed schools, especially in the first months, but this cannot be proven by the available fossil data," Fischer said.

In its shark heyday, the nursery area was full of nutrient-rich flora and fauna found within the bottom sediments. On the downside (from the shark's perspective), the large predatory fish Oshia, hungry amphibians, reptiles, and other animals also lived in the area and may have snacked on young shark eggs and infant sharks. There is no evidence that dinosaurs consumed the small sharks, but Fischer said that it is "possible, especially in lake environments."

Modern shark nurseries resemble this prehistoric one, except the one at Madygen was comprised of freshwater.

"There is no modern egg laying shark known to deposit egg capsules in a freshwater environment," he said.

Sep 7, 2011

Dolphins do not whistle, but instead "talk" to each other using a process very similar to the way that humans communicate, according to a new study.

While many dolphin calls sound like whistles, the study found the sounds are produced by tissue vibrations analogous to the operation of vocal folds by humans and many other land-based animals.

Communicating similar to the way that humans do solves what would otherwise be a major dolphin problem.

"When we or animals are whistling, the tune is defined by the resonance frequency of some air cavity," said Peter Madsen, lead author of the research appearing in Royal Society Biology Letters."The problem is that when dolphins dive, their air cavities are compressed due to the increasing ambient pressure, which means that they would produce a higher and higher pitch the deeper they dive if they actually whistle."

Madsen, a researcher in the Department of Biological Sciences at Aarhus University, and his team studied how dolphins communicate by digitizing and reanalyzing recordings made in 1977 of a 12-year-old male bottlenose dolphin.

The dolphin breathed in a "heliox" mixture consisting of 80 percent helium and 20 percent oxygen -- a concoction that causes humans to sound like, as the scientists put it, Donald Duck. The reason is because the mixture has a sound speed that's 1.74 times higher than normal air. If a person whistles after sucking in helium, the pitch of the tune will then be 1.74 times higher than if he or she whistles after breathing in just air.

"We found that the dolphin does not change pitch when it is producing sound in heliox, which means that its pitch is not defined by the size of its nasal air cavities, and hence that it is not whistling," Madsen said. "Rather, it makes sound by making connective tissue in the nose vibrate at the frequency it wishes to produce by adjusting the muscular tension and air flow over the tissue."

"That is the same way that we humans make sound with our vocal cords to speak," he added.

The researchers believe the finding applies to all toothed whales, since they have similar nasal anatomy and they "all face the same problem of making sound during deep dives."

In terms of what the dolphins are communicating, it's known they share information about their identity, helping them to stay connected even while traveling in vast bodies of water.

Acoustics engineer John Stuart Reid and Jack Kassewitz of the organization Speak Dolphin have created an instrument known as the CymaScope that reveals detailed structures within sounds, allowing their architecture to be studied pictorially.

Similar to deciphering Egyptian hieroglyphs, the researchers may then be able to figure out the meaning of dolphin calls. In addition to the whistle-like sounds, dolphins produce chirps and click trains, suggesting they engage in very complex and sophisticated social interactions.

"There is strong evidence that dolphins are able to 'see' with sound, much like humans use ultrasound to see an unborn child in the mother's womb," Kassewitz said. "The CymaScope provides our first glimpse into what the dolphins might be 'seeing' with their sounds."

Your wedding ring, the gold chain around your neck… even the platinum in your catalytic converter. For all of these you can thank a slew of meteorites that pelted Earth around 3.9 billion years ago, says new research.

Certain metals like gold, platinum, nickel, tungsten and iridium are attracted to iron, which comprises the Earth's core. So when the Earth first formed as a molten mass, all of these elements should have migrated to the core, leaving the outer layers of Earth stripped of its precious metals.

Yet as hopeful '49-ers knew, Earth's crust is laced with these enticing elements. Geologists have posed several theories to explain this puzzle, but one suggests that Earth was bombarded with meteorites between 3.8 and 4 billion years ago, studding the early crust with our favorite shiny metals. These metals then became incorporated into the modern mantle over time.

This idea is supported by the presence of craters on the moon, which date back to the same time, suggesting that the moon was also hit. Now, research published today in Nature, provides further evidence in favor of this explanation.

A team led by Matthias Willbold of the University of Bristol, U.K., sampled ancient rocks from southwest Greenland that formed some of the Earth's earliest crust, predating the proposed bombardment, and compared those with newer rocks from other places representing the modern mantle.

The researchers found distinct differences in the concentrations of particular tungsten isotopes in each type.

"This is a sort of a time capsule that gave us the possibility to calculate how much material had to be added to the Earth to satisfy the tungsten isotopic composition that we find in the Earth today," Willbold said.

"It is so far the best isotopic or geochemical evidence that late bombardment ever happened," he added.

"Our ability to measure these (isotopes) precisely enough to see these differences is just opening a totally new window into early planet formation," said Richard Carlson of the Carnegie Institution of Washington who has also studied early Earth using isotopes.

Unraveling the mystery surrounding the shipwreck found last year during excavations of the World Trade Center site has resulted in several facts as well as theories. The 18th century vessel, likely a single-masted sloop, measured approximately 50 feet long, and had a shallow, double-ended draft aided by a small, tapered keel built of squared-off hickory that that ran from stem-to-stern. The hull was built from Philadelphia oak trees -- one of which had lived for at least 111 years and was still growing in 1773, its youngest sapwood preserved in one of the boat's timbers.

Maritime historian Norman Brouwer had suggested that the unusually crafted sailboat was from a small rural shipyard and the trees for its timber from the same forest. "The data we see suggest something very similar," says Neil Pederson of the Lamont-Doherty Earth Observatory's Tree Ring Lab in Palisades, NY. "It's an interesting intersection in experts," he told Discovery News. He was part of a four-person dendrochronology team from the Tree Ring Lab working on samples of the vessel's white oak planks and its hickory keel. Other tree species used in the boat's construction included spruce and southern yellow pine, reported wood deterioration researcher Robert Blanchette of the University of Maine.

Looking up tree ring patterns for white oak timber samples is like hunting down a family's genealogy. To get the most accurate result, teams of people around the world need to have already done the manual labor of counting rings and entering forest timber chronologies into a database. Then it's a matter of sleuthing through generations of tree life-cycles to find a pattern that fits: where the timber samples and the trees share the same local climate of wet and dry years allowing them to make matching patterns of wide rings and skinny rings. So where to start?

An oak sailboat in New York could have originated anywhere in Europe or North America. Dutch ships original carried sloops across the Atlantic in the 1600s. Whose side was this sailboat on? Pederson said when they first heard of the find they weren't sure if they could track the soggy wood - when the team saw the keelson, the upper floor of the hull, the planks looked like white oak. When Blanchette confirmed their suspicions but added that they'd be getting a sample of hickory from the keel, the tree-ring team were relieved. The hickory keel sample was key - "it's been extinct in Europe for two million years or so," Pederson said.

So once the team did their own grueling process of slowly drying the timbers, waiting to see if the wood would decay, then sanding the samples, and counting the rings, sometimes as thin as one thousandth of a millimeter, and hoping each sample would provide at least 100 years of rings to make the sample comparable to other chronologies then the scientists got started looking for a match. They used a computer system to compare their samples with chronologies of forests from the New York State's Hudson Valley and then took a stab at a historical timber chronology they have from Philadelphia, "and that just about nailed it – really good," said Pederson.

When the wreck was first found the archeologists were confused as to whether they were looking at the front (stem) or back (stern) of the vessel. Turns out the sloop was rounded at both ends. Last month the Port Authority of New York and New Jersey excavated behind a concrete wall, where archeologists from the firm AKRF hoped to find remnants from the bow, where the figurehead and bowsprit thrust forward over the curving stem, the part of the sailboat that forms a bowshock of cresting waves and a good place to look for dolphins when under sail.

Eventually AKRF did recover a large portion of the structural part of the front of the boat. Now that material is with the Center for Maritime Archaeology and Conservation at Texas A&M University, where Director Kevin Crisman and his team are assisting the excavators with storage of the timbers. Alum and archeologist Carrie Fulton, now at Cornell University, spent a week cleaning, inspecting, and recording the new finds using stereophotography to generate 3D models.

One image shows part of the Roman numeral II, a draft mark carved into the lower stem indicating the point where the vessel was two feet from the bottom of the keel. With light loads this mark would likely hover just at the water line indicating to the crew that they would run aground if they traveled through water that was less than two feet deep, an event they likely did often.

Earth experienced its most dramatic extinction crisis of all time 250 million years ago when about 90 percent of ocean-dwelling species and 70 percent of land-dwellers disappeared. Exactly what caused the massive die-off, however, has long been a matter of debate.

Now, a new study offers new clues.

Ocean acidification caused by rising levels of carbon dioxide in the air, the study suggests, may have played a major role in the ancient extinction event, which was particularly hard on marine creatures that make calcium carbonate shells -- a process that's much harder for them to do in acidic conditions.

The findings have potentially major implications for what we can expect to happen on Earth in the near future. As atmospheric CO2 levels rise in the coming decades and the oceans absorb the gas, which ends up making the water more acidic, we might be headed for another round of serious extinction events.

"While it's hard to actually quantify the magnitude of the role played by ocean acidification compared to many other things going on, our results clearly show that ocean acidification played a role and maybe an important role in this extinction event," said Alvaro Montenegro, a physical oceanographer at St. Francis Xavier University in Nova Scotia.

"It is quite evident that we have pushed and continue to push the oceans toward more acidic conditions, and we already can foresee impacts on certain types of ocean organisms become significant quite soon," he added, with clams, mussels and other shellfish at biggest risk. "Our results are showing that organisms don't necessarily adapt quickly or quick enough to changes in ocean pH."

The history of life on Earth has been punctuated by a number of major extinction events, including the one that knocked off most of the dinosaurs about 65 million years ago. By far the most extreme sequence of events, though, struck just over 250 million years ago.

Now called the Permian-Triassic Boundary (PTB) extinction, it was unique in a few ways. Besides killing so many species both on land and in the water, for example, it was the only known extinction that wiped out a lot of insects, too. Unlike other extinction episodes, the cause of the PTB event is also surrounded by mystery. There is, for instance, not convincing evidence for a major meteor impact like the one that killed the dinosaurs.

Scientists do know that gigantic volcanic eruptions were spitting large amounts of methane and CO2 into the air at the time. Temperatures were very warm. And the geological record shows that parts of the seafloor were very low in oxygen. But it is still not clear what caused what.

To begin to untangle some of the mystery, Montenegro and colleagues created a computer model that simulated conditions before and during the extinction. The model included a historically accurate arrangement of continents. It also, for the first time, included a seafloor that was full of ridges and other sculpted features to create a realistic picture of water circulation patterns.

After setting temperatures and CO2 concentrations to the high levels that are thought to have existed at the time, the researchers ran experiments to see what would happen in the oceans.

Results, published in the journal Paleoceanography, showed that a warm climate couldn't explain documented changes in the oceans during the PTB extinction. Instead, high CO2 levels alone could have accounted for the serious drop in ocean pH.

Sep 6, 2011

A natural yellowing of the eye lens that absorbs blue light has been linked to sleep disorders in a group of test volunteers, according to a study in the September 1 issue of the journal Sleep. As this type of lens discoloration worsened with age, so did the risk of insomnia.

"The strong link between lens yellowing and age could help explain why sleep disorders become more frequent with increasing age," said Line Kessel, M.D., Ph.D., the study's lead author.

In the Danish study, 970 volunteers had their eyes examined by lens autofluorometry, a non-invasive method for determining how much blue light is transmitted into the retina. Blue light is a portion of the visible-light spectrum that influences the normal sleep cycle by helping initiate the release of melatonin in the brain. Melatonin is a hormone that helps signal to the body when it is time to be sleepy or alert.

Volunteers were considered to have a sleep disorder if they confirmed that they "often suffer from insomnia" or if they purchased prescription sleeping pills within the last 12 months. Of those classified as having a sleep disturbance, 82.8 percent affirmed that they both suffered from insomnia and used sleep medication.

Using this data, researchers calculated an inverse relationship between blue light transmission and the risk of having sleep disturbances: the lower the blue light transmission into the retina due to a yellowing of the eye lens, the greater the risk of sleep disturbances.

"The results showed that while age-related lens yellowing is of relatively little importance for visual function, it may be responsible for insomnia in the elderly," said Kessel, a senior scientist in the Department of Opthalmology at Glostrup Hospital in Denmark.

Significantly higher rates of sleep disorders were reported by older participants, women, smokers and those with diabetes mellitus. Previous studies have shown that the rate of lens aging is accelerated in smokers, patients with diabetes mellitus and those at high risk for ischemic heart diseases. The Danish researchers addressed these factors in their statistical analyses.

"The association between blue light lens transmission and sleep disturbances remained significant even after we corrected for age, sex, diabetes mellitus, smoking and the risk of ischemic heart disease," Kessel said.

She said another important factor to consider is that sleep quality has been shown to improve after cataract surgery. "The transmission of blue light currently cannot be improved by any other method than cataract surgery. I´m involved with another research project where we try non-invasively to remove the yellow color of the lens using a laser, but the method is not yet developed for clinical use," Kessel said.

After an 18-month shutdown to upgrade the machine and four months of commissioning, the Joint European Torus (JET), the world's largest magnetic fusion device, is ready to start new experiments. The inside of the vessel now has a completely new wall. JET is the first fusion machine to test the materials that will be used inside the next-generation international experiment, ITER.

Last Friday, scientists from throughout Europe started the first experimental campaign at JET after the installation of the "ITER-Like Wall." The upgrade comprises new materials inside the JET vessel, more heating power and additional diagnostic systems.

JET's researchers are investigating the potential of fusion power as a safe, clean, and virtually limitless energy source for future generations. The research is coordinated under the European Fusion Development Agreement (EFDA).

EFDA Leader Francesco Romanelli commented: "This is probably the largest effort that has been put into JET apart from the construction of the machine itself. With the expertise and contribution of many fusion laboratories, the JET team has succeeded in building a small ITER. We had a very good start with high purity plasmas readily established in ITER relevant conditions -- a promising sign for the use of these wall materials in ITER."

The inside of the JET vessel is now made of beryllium and tungsten tiles forming an 'ITER-Like Wall'. Between October 2009 and May 2011 engineers from Culham Centre for Fusion Energy removed and replaced approximately 86,000 components, largely using remote handling technology.

Lorne Horton, Head of EFDA's JET Department, explained: "The coming experiments will aim to verify that the wall materials chosen for ITER will behave as expected." Beryllium is being used in the main wall, whereas tungsten, with its high melting point, is the choice for the exhaust component known as 'divertor' that has to withstand high heat flux.

The other main enhancement is a 50% increase in the heating power. With the extra power, JET will achieve higher plasma temperatures and approach ITER conditions. New diagnostics and control systems, developed by the EFDA associate laboratories, will allow a deep investigation of the scientific challenges in preparing for ITER.

Maximos Tsalas is one of the visiting scientists in the control room. He has worked for many years at JET and has recently moved to FOM Rijnhuizen, in The Netherlands. He explained: "I left JET more than a year ago. Coming back, the developments I see are amazing. JET has become a brand new machine. I feel extremely privileged to take part in the first set of experiments. The coming campaign will be very challenging, and we are all eager to see how the new systems perform and to learn how to operate with the new wall."

Filmmakers Jules and Gedeon Naudet and were supposed to be making a documentary about New York City firefighters, following a probie named Tony Benetatos as he went from the academy to his assignment with Ladder 1.

Instead, on that September morning in 2001, they were witnesses to history.

Their documentary "9/11" aired on CBS in 2002. To mark the 10th anniversary of the terrorist attacks, the French-born brothers – along with co-director James Hanlon – have updated the film.

Titled "9/11: 10 Years Later," the filmmakers will look into the lives of the firefighters who appeared in the original documentary, as well as some of the ongoing health problems of the first responders. They will also tour the ongoing construction efforts at Ground Zero.

The Naudet footage is still some of the most comprehensive on-site coverage of the World Trade Center attacks and rescue attempt.

Jules Naudet was with the battalion on a routine call about a gas leak when American Airlines Flight 11 slammed into the North Tower of the World Trade Center. The sound of the incoming plane, as well as the collision, is caught on camera, as are the firefighters’ uncensored reactions.

As Jules headed with the unit to the North Tower, his brother Gedeon filmed reactions both back at the firehouse, and of the crowd on the street just below the World Trade Center. He also captured the impact of United Airlines Flight 175 as is crashed into the South Tower.

Nuclear physics might soon solve a longstanding Leonardo da Vinci mystery -- the fate of a lost masterpiece known as the "Battle of Anghiari."

The project, one of the most ambitious in art history, involves developing a unique camera that can take photographs through a 5-inch-thick wall.

The brick barrier is no ordinary wall. It stands in Palazzo Vecchio, Florence's 14th-century city hall, in the imposing Hall of Five Hundred, and houses a mural known as the "Battle of Marciano." It was painted by the renowned 15th-century painter, architect and writer Giorgio Vasari.

Leonardo's lost work could lie right behind that wall, according to art diagnostic expert Maurizio Seracini, director of the Center of Interdisciplinary Science for Art, Architecture and Archaeology at the University of California, San Diego.

The long-lost fresco, which Seracini has been searching for since the 1970s, has a mysterious history. It was conceived in 1503, when Leonardo and Michelangelo received twin commissions to paint historic Florentine victories on opposite walls of the Palazzo Vecchio in Florence.

While Michelangelo never got past a sketch of his "Battle of Cascina," Leonardo began to paint the centerpiece of the ''Battle of Anghiari," known as the ''Fight for the Standard," on June 6, 1505, when he was 53.

"Representing vividly the rage and fury both of the men and the horses," as Vasari wrote in his 1550 book "Lives of the Artists," the 12- by 15-foot mural would celebrate the Florentine's victory over Milanese troops in 1440.

Vasari (1511-1574) reported that Leonardo abandoned the project because of technical problems arising from his experimental mixing of oil paint and fresco.

Historians, however, have questioned Vasari's conclusion. Some speculated that he made up the story, and that the fresco actually was completed.

Hailed by Leonardo's contemporaries as his finest work, the "Battle of Anghiari" now survives in several preparatory drawings and sketches by the master himself and in a Rubens drawing which was inspired by an anonymous copy of the fresco.

Ten years after writing his account of the "Battle of Anghiari," Vasari was hired to modify the council room into the Hall of Five Hundred, a hall dedicated to the ruling Medici family.

In the course of this work, Leonardo's mural disappeared. The council room remodeling was part of a city-wide renovation plan devised by Duke Cosimo I to celebrate the Medici family.

As part of this project, Vasari also modified the church of Santa Maria Novella, covering up the 1428 Masaccio fresco "Trinità" with a wall on which he painted a panel of the "Madonna of the Rosary."

Masaccio's work remained obscured until 1861, when Vasari's wall was removed.

In 2000, at a Da Vinci conference, leading scholar Carlo Pedretti proposed that Vasari saved Leonardo's masterpiece just as he had Masaccio's.

The conference prompted Seracini to carry out sophisticated tests that used laser scanners, X-ray machines and thermographic and radar equipment.

First he reconstructed the plan of the hall before Vasari's remodeling by finding the original windows and doors, now covered by walls. Then he focused on Vasari's work.

Sep 5, 2011

It is now widely accepted that the species Homo sapiens originated in Africa and eventually spread throughout the world. But did those early humans interbreed with more ancestral forms of the genus Homo, for example Homo erectus, the "upright walking man," Homo habilis, -- the "tool-using man" or Homo neanderthalensis, the first artists of cave-painting fame?

Direct studies of ancient DNA from Neanderthal bones suggest interbreeding did occur after anatomically modern humans had migrated from their evolutionary cradle in Africa to the cooler climates of Eurasia, but what had happened in Africa remained a mystery -- until now.

In a paper published in the Proceedings of the National Academy of Sciences (PNAS), a team led by Michael Hammer, an associate professor and research scientist with the the University of Arizona's Arizona Research Labs, provides evidence that anatomically modern humans were not so unique that they remained separate.

"We found evidence for hybridization between modern humans and archaic forms in Africa. It looks like our lineage has always exchanged genes with their more morphologically diverged neighbors," said Hammer, who also holds appointments in the UA's department ofecology and evolutionary biology, the school of anthropology, the BIO5 Institute and the Arizona Cancer Center.

Hammer added that recent advances in molecular biology have made it possible to extract DNA from fossils tens of thousands of years old and compare it to that of modern counterparts.

However, "We don't have fossil DNA from Africa to compare with ours," he said. "Neanderthals lived in colder climates, but the climate in more tropical areas make it very tough for DNA to survive that long, so recovering usable samples from fossil specimens is extremely difficult if not impossible."

"Our work is different from the research that led to the breakthroughs in Neanderthal genetics," he explained. "We couldn't look directly for ancient DNA that is 40,000 years old and make a direct comparison."

To get past this hindrance, Hammer's team followed a computational and statistical approach.

"Instead, we looked at DNA from modern humans belonging to African populations and searched for unusual regions in the genome."

Because nobody knows the DNA sequences of those now extinct archaic forms, Hammer's team first had to figure out what features of modern DNA might represent fragments that were brought in from archaic forms.

"What we do know is that the sequences of those forms, even the Neanderthals, are not that different from modern humans," he said. "They have certain characteristics that make them different from modern DNA."

The researchers used simulations to predict what ancient DNA sequences would look like had they survived within the DNA of our own cells.

"You could say we simulated interbreeding and exchange of genetic material in silico," Hammer said. "We can simulate a model of hybridization between anatomically modern humans and some archaic form. In that sense, we simulate history so that we can see what we would expect the pattern to look like if it did occur."

According to Hammer, the first signs of anatomically modern features appeared about 200,000 years ago.

First, the team sequenced vast regions of human genomes from samples taken from six different populations living in Africa today and tried to match up their sequences with what they expected those sequences to look like in archaic forms. The researchers focused on non-coding regions of the genome, stretches of DNA that do not contain genes, which serve as the blueprints for proteins.

"Then we asked ourselves what does the general pattern of variation look like in the DNA that we sequenced in those African populations, and we started to look at regions that looked unusual," Hammer said. "We discovered three different genetic regions fit the criteria for being archaic DNA still present in the genomes of sub-Saharan Africans. Interestingly, this signature was strongest in populations from central Africa."

The scientists applied several criteria to tag a DNA sequence as archaic. For example, if a DNA sequence differed radically from the ones found in a modern population, it was likely to be ancient in origin. Another telltale sign is how far it extends along a chromosome. If an unusual piece is found to stretch a long portion of a chromosome, it is an indication of being brought into the population relatively recently.

"We are talking about something that happened between 20,000 and 60,000 years ago -- not that long ago in the scheme of things," Hammer said. "If interbreeding occurs, it's going to bring in a whole chromosome, and over time, recombination events will chop the chromosome down to smaller pieces. And those pieces will now be found as short, unusual fragments. By looking at how long they are we can get an estimate of how far back the interbreeding event happened."

The fuzziness and weird logic of the way particles behave applies surprisingly well to how humans think

THE quantum world defies the rules of ordinary logic. Particles routinely occupy two or more places at the same time and don't even have well-defined properties until they are measured. It's all strange, yet true - quantum theory is the most accurate scientific theory ever tested and its mathematics is perfectly suited to the weirdness of the atomic world.

Yet that mathematics actually stands on its own, quite independent of the theory. Indeed, much of it was invented well before quantum theory even existed, notably by German mathematician David Hilbert. Now, it's beginning to look as if it might apply to a lot more than just quantum physics, and quite possibly even to the way people think.

Human thinking, as many of us know, often fails to respect the principles of classical logic. We make systematic errors when reasoning with probabilities, for example. Physicist Diederik Aerts of the Free University of Brussels, Belgium, has shown that these errors actually make sense within a wider logic based on quantum mathematics. The same logic also seems to fit naturally with how people link concepts together, often on the basis of loose associations and blurred boundaries. That means search algorithms based on quantum logic could uncover meanings in masses of text more efficiently than classical algorithms.

It may sound preposterous to imagine that the mathematics of quantum theory has something to say about the nature of human thinking. This is not to say there is anything quantum going on in the brain, only that "quantum" mathematics really isn't owned by physics at all, and turns out to be better than classical mathematics in capturing the fuzzy and flexible ways that humans use ideas. "People often follow a different way of thinking than the one dictated by classical logic," says Aerts. "The mathematics of quantum theory turns out to describe this quite well."

It's a finding that has kicked off a burgeoning field known as "quantum interaction", which explores how quantum theory can be useful in areas having nothing to do with physics, ranging from human language and cognition to biology and economics. And it's already drawing researchers to major conferences.

One thing that distinguishes quantum from classical physics is how probabilities work. Suppose, for example, that you spray some particles towards a screen with two slits in it, and study the results on the wall behind (see diagram). Close slit B, and particles going through A will make a pattern behind it. Close A instead, and a similar pattern will form behind slit B. Keep both A and B open and the pattern you should get - ordinary physics and logic would suggest - should be the sum of these two component patterns.

But the quantum world doesn't obey. When electrons or photons in a beam pass through the two slits, they act as waves and produce an interference pattern on the wall. The pattern with A and B open just isn't the sum of the two patterns with either A or B open alone, but something entirely different - one that varies as light and dark stripes.

Such interference effects lie at the heart of many quantum phenomena, and find a natural description in Hilbert's mathematics. But the phenomenon may go well beyond physics, and one example of this is the violation of what logicians call the "sure thing" principle. This is the idea that if you prefer one action over another in one situation - coffee over tea in situation A, say, when it's before noon - and you prefer the same thing in the opposite situation - coffee over tea in situation B, when it's after noon - then you should have the same preference when you don't know the situation: that is, coffee over tea when you don't know what time it is.

RADIATION therapy to treat cancer is more effective in some people than others. A new discovery that reveals why could help to boost effectiveness of the therapy and reduce related radiation sickness.

Vivian Cheung at the University of Pennsylvania in Philadelphia and colleagues exposed cells from 99 healthy individuals to a dose of radiation that prompts a cellular response similar to what happens during therapy. Following the dose, the activity of caspase - an "executioner" enzyme that causes cells to self destruct - increased by between 120 and 720 per cent, confirming that people respond differently to treatment.

The team also looked at gene expression before and after exposure and identified 335 genes whose variation in expression correlated with caspase activity. Silencing five genes whose expression negatively correlated with caspase activity significantly increased cancer cells' sensitivity to radiation.